What dose of Mounjaro is equivalent to Wegovy 2.4 mg?

Why there is no clean dose-to-dose conversion between Mounjaro and Wegovy

Mounjaro (tirzepatide) activates both the GIP and GLP-1 receptors simultaneously. Wegovy (semaglutide) targets the GLP-1 receptor only. Because those mechanisms are genuinely different, comparing doses is a bit like comparing the speed of two different engines by looking at the fuel grade alone, the numbers overlap in some places, but the underlying chemistry does not.

Mounjaro's licensed schedule runs from 2.5 mg through to 15 mg in six steps. Wegovy's standard maintenance dose is 2.4 mg weekly, reached after a graduated titration that begins at 0.25 mg. If you are thinking about switching between them (or trying to understand where you would start if you moved from one to the other) the honest answer is that no published conversion table exists. A prescriber considers which dose to begin at based on what you were taking, how long you were on it, and how your body responded.

The broader Mounjaro to Wegovy dose conversion question is explored in more detail on a dedicated page, but the short version is that switches are managed clinically, not arithmetically. Our clinical team reviews every transfer patient's evidence before any dose is confirmed.

What the trial evidence says about Wegovy 2.4 mg and the Mounjaro doses that come close

The STEP 1 trial, published in the New England Journal of Medicine, found that semaglutide 2.4 mg produced around 15% average body-weight reduction over 68 weeks in adults with obesity and no diabetes. That is the benchmark for Wegovy's standard maintenance dose.

In the SURMOUNT-1 trial, tirzepatide at 10 mg produced average weight loss of around 19.5% over 72 weeks, and at 15 mg the figure rose to roughly 20–21%. The head-to-head SURMOUNT-5 trial, published in the New England Journal of Medicine in 2025, directly compared tirzepatide with semaglutide 2.4 mg over 72 weeks and found greater average weight reduction with tirzepatide. NICE's appraisal of tirzepatide (TA1026) references this indirect and direct evidence when discussing the relative clinical effectiveness of the two medicines.

The practical upshot: if Wegovy 2.4 mg is roughly equivalent to anything on the Mounjaro ladder, the evidence points toward the mid-to-higher doses (10–15 mg) in terms of average weight loss, but individual response varies considerably, and no prescriber would simply jump a transfer patient to those doses. For context on where specific Mounjaro doses sit relative to Wegovy, our page explaining what dose of Wegovy is equivalent to 7.5 mg of Mounjaro explores that particular comparison in depth, including how the 7.5 mg Mounjaro dose maps onto Wegovy when patients are mid-titration and weighing their options.

The comparison in numbers: a factual reference table

The table below summarises the key trial figures and licensed context for both medicines at the doses most relevant to this comparison. All numbers are from clinical trial data and should be read as population averages, not individual predictions.

These are averages across thousands of trial participants. Some people do better on semaglutide; some do not tolerate tirzepatide's titration. The cost comparison between the two is a separate and practical question worth considering alongside the clinical one.

Which medicine to choose, and why that question belongs with a prescriber

The decision between Mounjaro and Wegovy is genuinely clinical. Both are licensed in the UK for weight management in adults with a BMI of 30 or above, or 27 or above with at least one weight-related health condition such as high blood pressure, type 2 diabetes or high cholesterol. Lower BMI thresholds apply for some ethnic backgrounds under UK guidance. But eligibility alone does not settle the question: your GP history, any medicines you already take, your preference for injection or the new oral option, and how your body handled previous treatment all matter.

If you are currently on Wegovy 2.4 mg and wondering whether switching makes sense, or if you are new to treatment and weighing the two up, the starting point is a free consultation. For anyone already on Wegovy and curious about what the lower Mounjaro doses look like by comparison, the page covering the Wegovy equivalent to Mounjaro 2.5 mg puts the starter dose in context.

When treatment is approved, the medicine arrives from our GPhC-registered pharmacy via DPD the next working day, in plain packaging with no branding on the outside, the pen itself comes in the manufacturer's box, with the Patient Information Leaflet, ready to store in your fridge. Our prescribers are available seven days a week if you have questions after it arrives. Start your free consultation and our clinical team will work through which medicine and which dose makes sense for you specifically.